Power-operated, predetermined torque release wrench



May 26, 1953 w. H. PEcK 2,639,636

POWER-OPERATEU, PREDETERMINED TORQUE RELEASE WRENCH Filed March 8, 1951 2 Sheets-Sheet l 4 /zz l E* 7 8 IN VEN TOR. A//zz/M /ifc/r May 26, 1953 w. H. PECK 2,639,636

` POWER-OPERATED, PREDETERMINED ToRQUE RELEASE WRENCH Filed March 8, 1951 2 sheets-sheet 2 Afro/mfr Patented May 26, 1953 OFFICE POVVER-OPERATED, PREDETERMINED TORQUE RELEASE WRENCH William H. Peck, Royal Oak, Mich.

Application. March s, 1951, seialNo. 214,485

7 Claims. .1 I This invention relates to a tool and more particularly to a power driven tool for turning nuts,

bolts, screws and the like, commonly referred to as a torque wrench. More specifically, the invention relates to improvements in a device disclosed in my pending application, Serial Number 138,348, led January 13, 1950.

It is an object of the present invention to provide a power driven tool wherein torque power, used in turning the work, is dissipated or utilized for producing reciprocating movement of a part, upon reaching a predetermined resistance, so that the turning force is arrested. after a predetermined` power has been reached.

Another object of the invention is to provide J improved means for varying the torque resistance so that the operator mayhave a selection of torque power ranges.

A further object of the invention is to provide improved cooling means for the working parts of the device to remove the heat generated by the conversion of torque motion into reciprocating motion.

A still further object of the invention is to provide an arrangement of parts which may be easily assembled, adjusted, and one in which the parts may be economically manufactured.

Other objects and advantages of the invention y' will more fully appear from the following description taken in connection with the accompanying drawings, in which:

Fig. 1 is a side elevational View of a tool em- Y showing the reciprocating member and its ,cam`

follower members in side elevation;

Fig. 4 is a cross sectional view taken on line y4 4 of Fig. 2;

Fig. 5 is a cross sectional View taken on line 55-5 of Fig. 2;

Fig. 6 is a cross sectional view taken on line 6--6 of Fig. 2;

Fig. '7 is a cross sectional view taken on line l--l of Fig. 2; and

Fig. 8 is a cross sectional view taken on line 8--8 of Fig. 2.

Referring to the drawings, I have shown the tool having a body portion 2l! in which an electric motor is mounted for power driving means to a transmission housing 22. The body portion 2li is provided with a handle 24, a finger control switch 26 and an electrical lead 28,. The translio mission housing 22L is provided with an internally threaded 'sleeve 30 which receives the housing of my improved device.

A casing 32, enclosing the working parts of the mechanism, is screw threaded into the sleeve 30. A drive shaft 34, in the transmission'housing 22, is adapted for driving engagement with the drive shaft 36 of the driven torque'conversion mechanism, shown in the form of an adapter t'o be applied to the power driving means.

The adapter has a cylindrical sleeved bushing 38 fitting the interior of the casing 32. The inner periphery of the casing 32'is provided with inwardly extending shoulders 40 which receive slotted anges 42 extendingV outwardly Ifrom the inner periphery c f the casing 32 and from the outer periphery of the` rotatable member 46 and the wall is provided -with` openings 48 therethrough. The openings '4S together with the slottedflanges 4 2 provide for -a circulation of air around the rotatable member 46' and between the member 46 and casing 32 for cooling.

The shaft 36, at yits inner end, has a hexagonal portion l50 whichrreceives a coupling 52. The i coupling '52V has al hexagonalV opening 54 which ts over the hexagonal end 50 and also has oppositely andjradially extending flanges 56 whichr form driving lugs forengagementwith driving lugs58 carried by the drive shaft 34 of the transmission.

The vshaft 36 has its main body portion formed for drivin'g'connection withi'a sliding piston 60.' This driving connection is "shown as a hexago.". nal portion 62 slidably fitting' a correspondingly shaped inner surface of the piston 60, but the shaft and piston may have the usual'spline con- 1 nection or other drive means which will permit relative sliding'movement of the piston-on the shaft.4 The opposite end faces of the piston 6I '1 are provided with cam tracks E4 which engage cam followers 66 and 68 on insert rings lll and Y l2. The rings'l and'lZ are rotatable relative to the shaft 36 but arekeyed to the rotatable member 4S, the ring 10 held to the rotatable member 46 by pins T4 in yslots 'I6 and 'I8 of ring The cam followers 66 and 68 space the rings 'l0 and 'l2 Vfrom the opposite ends of the piston 60 providing fluid chambers 86 and 88 which are intercommunicating through a longitudinal passage 90, in the shaft 36, and radially extending passages 92 and 94 through the wall of the shaft 36. A groove 96 in the outer periphery of the piston 60 forms a iiuid reservoir which is in com- 5 munication with one of the chambers 86 or 88 by a passage 98, here shown connected to the chamber 94.`= rA iillr (plugii in the rotatable member 46 provides* a means for vsupplying uidf to the chambers 86, 88 and reservoir 96. The 10 ller plug |00 further provides a means for removing the air from the chambers-and passages.Vr when the fluid is supplied to the'chambers.

The outer end of the shaft 36 is journaled in a bushing |02 carried by the rotatable rnemfberfw `"l5 The longitudinal passage 90 extends through the outer end of the shaft 36"and receives a needle valve |04 having a cylindrical shank'lportion |06 and a tapered iner end portion |08. The fineedleavalve |104 is serewfthreadedf. inte -a 20 plug 0 whichl is screvvffthreadediintoftherouter?.g i end of the rotatablemember 46a-:The plug-M0 mayf? be irernovecifwith theneedle fvalve" 04 andi thetaxialeposition' of .thel-.needleU-valve -rnay-be s adjusted -relative theretov'so 'vthatfwh'en' the .plug- 25 andmeedlel valve arefin Apositionwthe amount-oi owffromfpassagefO to passage :94;v or l*from'pas-wV sage:94 -t`o passage =90,fmay be predetermined-dafpendent upon the position of-tapered-.end.-portion |08 of'i'the" needle=valvefwith^respeetto the-pasa- 30 sagei'84.

At `fthefinner end of the rotatable member -46 is a cylinder cap I|2,h,eld:on themember 48 ybye/- a G: ringV |1| 4 tting oppositely positionedgrooves w in the-member 'andthefcap-Hf- Sealing gasf- 35 ketsflPIB and H8 are provided between'thelmembe1e46and the capi-I I2 to sealthefluidr chambers--l 90,f,92,'194 and196 .againstiuidfleakw A plural-ityof 'insfI-'E -are provided onthecap-f-I |2- toV create a 'circulationf-of lain-through :thefffcasi-ngf 32, 4o Openings |22 .and :|24 are providedfor yadrnit; tingand expelling-the'airfwhichpas before stated,` is permitted'to `flow through-:the slots 42=and openingsr48fof thebushing-r-t At *thefouterfend'of thevcasingf=32 is a sliding@ tool supporting member-i2Sjournaled-in a bush` -45 ingoi-Zdf-:There is alsofa bearing ddii-between theftool supporting :member P |26 Iandtherouter,h endfof .thef'rotatarble housing-46. The inner-end f of the'toolrsupportng member-is provided with' jaw clutch' membersI |32,l betten -fs-hown in Fig. y8, v50 for Eengaging j aw7 clutchl f members |34; 1on1. the outer 'end' Aoi the rotatable member 46: v- A com- H' pression spring |36 between the outer end of vthe@l plug-H0 and'theftooltsupportingf member |26 normally 'holds' vthe iawclutch7 members i vdisen! 55 gagedrso 'that driving @torque from they rotatable member f46ris not transmittedato -thev toolvfsupt,l portingmember |2 6.t KThe tool- |38,-hereinshown as a2 screwfdriver, Yhas "af driving connection with the' outer nd of the tool-supporting member-and 60 is retained'thereon' by a spring' pressed :ball |40 f betweerrtthe: tool" 'andf the -ftool supporting` -memherz-l-When'it is desiredto -drive'lthetool from.n therrotatablememberfr axial pressurefis apy i plied "to the 'tooliand the tool supporting-1mem-berf-65 movesinwardly and the-*jaw clutches lare' interengagdj f" A sealing' gasket' |42 -is provided between the plug-||0 and the rotatable membe1f-46 to prevent fluid leak-from the-duid lchambers 00,A4 92,'A 94 70 and-96.----

y. Assuming now that it is desired to fdrivethe tool under full torque load, the needle'valvejl'04 is adjusted't'o an axial`positiowheie"thcy" lindrical shank portion |06 of the valve com- 75 pletely closes the radial passages 94 so that no uid can be moved from one chamber 88 to the other chamber 86. This balanced pressure in the two chambers prevents axial movement of the piston 60. The torque of the drive shaft 34 then rotates the shaft 36, through coupling 52, and the shaft 36 in turn rotates the piston 60. Since the'pist'oriG can notvbe moved axially due to thesta-ticfluidin the-chambers 486 and 88 the torque force of the piston 60 rotates the rings? 'l0 and 'l2 through cams 64 and their respective followers. V66 and 68. The rings 10 and l2 A'areifkeyed--t'o therotatable member 46 and impart aturning force to the member 46 which bers |32 and |34 are engaged by the axial pressure above referredlto.

Now, if it is desired to reduce the torque force to a predetermined forcel applied to the tool romnthatof theftorqueY force of the driving membrfthelneedlefvalve 04 'is adjusted, s'o that' the-tapered portioiilwll vpermit-a flow'of fluid' through,=the2fpassag."94`to the' chamber'90,

passage ,92 aidcha'mber! 86,61* lin a reverse' direc'- tion. to '.thelchainber 3.88.17,v 'This will permit vthe piston to reciprocate To'n .theshaft '36 'by'moving i the fluid `-from one'of the "chambers 86 or 88 .to

the-,otherwWlin the piston 60 'is permitted tb reciprocate'there is no rotary movement applied to therings l0 lT2 'and' therotatable 'member is notrotated. The torque power is thus converted from rotary movement of the piston t/o reciprocating movement and -therotatable memberis not rotated, consequently thereis no additional-torque,appliedito -the tool.

ThusVby adjusting the position of thelneedle work piece comprising, a rotatable-driven shaft a sleeve Amemberrotatably supported on said shaft and-surroundings, portion of said shaft, a piston-havingdtsouter periphery lslidably fitted to the-finner-periphery of saidsleeve, said piston being rotatable by said shaft and axially slida'ole thereo n,-end Wal-ls xed .to saidn sleeve forming with-saidi shaitandl said sleeve a fluid Chamber at each of the ends'of said-pistoma cam track on-.each-end\ffaceofsaidpiston, a cam followeron each end wall in co-operative engagement y Withsaid cam-track,- said fluid chambers having an intercommunioating fluid passage; means for restrictingfthe uidlow lthrough/,title viiuid-Y pas; sage, and a work piece carried by said sier-tive".`

2. toolifor" transmittingtorque power to a work piece comprising, a rotatable driven shaft,

a sleeve?v member f'rotatablysupportedon said shaft and surrounding a portion of said shaft, a pistoh'av'ingts outerperiphery slidabiy i'ltted to the-'innerperiphery of Vsaid sleeve, 'said piston beingrtatableby said shaft' and axially slidable thereon, end-'walls xed 'to said sleeve' forming with''said shaft 'and said sleeve' a fiuidfchamber at -e'ach of the end--of said piston, a cam track on each end face of said piston, a cam follower on each end wall in co-operative engagement with said cam track, said fluid chambers having an intercommunicating iiuid passage, variable means for restricting the fluid flow through the iiuid passage, and a work piece carried by said sleeve.

3. A tool for transmitting torque power to a work piece comprising, a rotatable driven shaft, a sleeve member rotatably supported on said shaft and surrounding a portion of said shaft, a piston having its outer periphery slidably fitted to the inner periphery of said. sleeve, said piston being rotatable by said shaft and axially slidable thereon, end walls xed to said sleeve forming with said shaft and said sleeve a fluid chamber at each of the ends of said piston, a cam track on each end face of said piston, a cam follower on each end Wall in co-operative engagement with said cam track, said cam followers being in axial alignment, said uid chambers having an intercommunicating fluid passage, means for restricting the fluid flow through the fluid passage, and a work piece carried by said sleeve.

4. A torque inverter comprising, a power drive shaft, a driven sleeve surrounding said shaft, a piston rotatably driven by said drive shaft and axially slidable on said shaft and within said driven sleeve, said piston forming with said sleeve and said shaft a fluid chamber at the opposite ends of said piston, a cam track at 'the opposite ends of said piston, cam followers xed to said sleeve in co-operation with said cam tracks, a fluid passage for conducting fluid from one of said fluid chambers to the other, and valve means for regulating the flow of iiuid through said passage.

5. A torque inverter comprising, a power drive shaft, a driven sleeve surrounding said shaft, a piston rotatably driven by said drive shaft and axially slidable on said shaft and within said driven sleeve, said piston forming with said sleeve and said shaft a fluid chamber at the opposite ends of said piston, a cam track at the opposite ends of said piston, cam followers fixed to said sleeve in co-operation with said cam tracks, a iiuid reservoir carried by said piston having a passage communicating with one of said cham- CFI bers, a iiuid passage for conducting fluid from one of said fluid chambers to the other, and valve means for regulating the flow of fiuid through said passage.

6. A device for transmitting torque power to a rotatable tool comprising, a driven rotatable shaft, a sleeve surrounding said shaft and rotatable relative thereto, a slidable piston rotated by said shaft and axially movable thereon, said piston dividing the space between said sleeve and said shaft into fluid chambers, one at each end of said piston, correspondingly shaped cam tracks, one at each end of said piston, a projection on the end wall of each chamber cooperating with an adjacent cam track for reciprocating said piston by relative rotation of said piston and said projections, a uid passage forming a communication between the chambers, and an adjustable valve for regulating the flow of fluid through said passage.

'7. A device for transmitting torque power to a rotatable tool comprising, an outer casing, a rotatable sleeve within said casing, a drive shaft within said sleeve, a piston rotatable with said drive shaft and slidable on said shaft and within said sleeve, cam means for reciprocating said piston by relative rotation of said piston and said sleeve, variable resistance means for preventing relative rotation of said piston and said sleeve, and a perforated bushing forming the bearing between said casing and said sleeve, said bushing being longitudinally slotted to permit a circulation of air through said bushing between said sleeve and said casing.

WILLIAM I-I. PECK.

References Cited in the le 0f this patent UNITED STATES PATENTS Number Name Date 2,384,399 Reynolds Sept. 4, 1945 2,398,392 Page Apr. 16, 1946 2,565,579 Thorner Aug. 28, 1951 FOREIGN PATENTS Number Country Date 53,643 Netherlands Dec. 15, 1942 

